The Bonding and Metalocene-Like Catalysis of Particulate and Fiber Reinforced Thermosets and thermoplastics Using Neoalkoxy Titanates and Zirconates

摘要

Enhanced fiber (aramid, graphite, polyester and glass), carbon black, CaCO_3 and mineral filled reinforced thermosets and thermoplastics may be achieved by the use of organometallic coupling agents based on titanium and zirconium. Typically, they can produce better bonded composites with superior processability, physical properties and environmental stability. A review of results obtained by the author and other investigators is offered demonstrating adhesion and metallocene-like catalysis effects. For example, N.Subramaniam et al reported a zirconate coupling agent (NZ) 37 had a measurable effect (11.2-20.3 MPa) on the interfacial shear strength of a Kevlar~direct R (Du Pont) fiber/phenolic composite from single strand pullout tests; R.Kraus et al studied the deformation of unfilled and glass fiber-reinforced ethylene tetrafluoroethylene copolymer (ETFE). Microcracking was observed by small-angle x-ray scattering (SAXS). The fibers induce local stress maxima and increase the formation of microcracks. Fiber delamination processes were monitored by acoustic emission analysis. The use of an aliphatic amino zirconate (NZ 44) improves the fiber-matrix adhesion and increases the mechanical yield stress and decreases the delamination process; Stanley A.Watson of DMT used 0.2 per cent of a phosphato titanate (LICA 12) to reduce the injection mold temperature requirements of 40 per cent fiberglass reinforced polycarbonate by 116 deg C while part quality and color was better and molded four seconds faster.